What is White Noise

White Noise Definition

Many people ask, What is White Noise and the answer is sometimes a little confusing because there is a technical, scientific definition and a more common and less rigorous popular definition. Technically, White noise is a sound containing a blend of all the audible frequencies distributed equally over the range of the frequency band. White noise is analogous to white light which contains all the colors of the rainbow together. The more common answer to What is White Noise, is that it can be natural white noise sounds like wind, rain, ocean waves, the sound of a waterfall or a mountain stream that approximates White Noise and has the ability to mask sounds.

How to Use White Noise

Because white noise contains all or most frequencies, it is commonly used to mask other sounds. If you are in a hotel and voices from the room next-door are leaking into your room, you might turn on a fan to drown out or mask the voices. Similar to rain or wind, the fan produces a good approximation of white noise. What is white noise, how does white noise work and why does white noise mask out other noises?

Here is one way to think about it. Let's say two people are talking at the same time. Your brain can normally pick out one of the two voices and actually listen to it and understand it. If three people are talking simultaneously, your brain can probably still pick out one voice. However, if 1,000 people are talking simultaneously, there is no way that your brain can pick out one voice. It turns out that the combined sound of 1,000 people talking together sounds a lot like white noise. This white noise, that contains all frequencies, happens to cancel out some of the other voices and sounds thereby making them difficult to hear. So when you turn on a fan to create white noise, you are essentially creating a source of 1,000 voices. The voice next-door makes it 1,001 voices, and your brain can't pick it out anymore. One thing to keep in mind when using white noise is that more is not always better - it is usually best to use just enough to help mask the offending noise, not completely overwhelm it.


Top Rated White Noise Devices

Follow links to find more information about What is White Noise.

You can go directly to the order page of the most popular White Noise Machine the Sleepmate 980A.

The mechanical devices produce a sound very close to that of a fan. The Top Rated of this type is the Marpac SleepMate 980A White Noise Machine. This device has been around for a long time and is by far the most popular of all white noise sounds. The SleepMate is a small cylinder (5.75" base diameter, 3.25" high) and produces sound mechanically (like a fan).

White noise can be generated with a digital sound synthesizing device. Sound designers, with some processing and filtering, can create a multitude of effects such as wind, rain, waterfall or surf. The main consideration when choosing a digital device is if the device loops a recorded clip of sound or synthesizes its own sound. By looping we refer to a few seconds of sound that is recorded and played over and over. They try to match up the end with the beginning but if you listen carefully you can detect where the segment begins - this is irritating to some people. The better digital sound devices actually synthesize the sound instead of playing a recording, therefore no looping.

Another answer to What is White Noise can be found in the Marpac white noise machines which synthesize their sound so there is no looping effect. Most sound machines play back a short recorded clip of sound that has been tailored to create a continuous loop.

HoMedics produces White Noise Sound Machines that, though they do have looping, it is hard to detect and they are less expensive than Marpac and represent a good value.

For a unique approach that will work for some people (particularily those with a snoring partner or other loud sounds), Sleep Eze makes a pair of tiny hearing-aid-like device that produces white noise sounds that actually fit in your ears.